Characterization of hay-like off-odor in basil samples after various processing and strategies for reducing the off-odor. (December 2022)

• Record Type: Journal Article
• Authors: Liang, Jiaqi; Shalaby, Nouran; Rigling, Marina; Wagner, Tim; Heimbach, Julia; Fries, Alena; Kohlus, Reinhard; Zhang, Yanyan
• Is Part Of: Food research international. Volume 162(2022)Part B
• Publication Date: 2022-12
• Subjects: Basil -- Off-odor -- 3-Methylnonane-2, 4-dione -- Sensory analysis -- Gas chromatography–mass spectrometry–olfactometry; Food -- Analysis -- Periodicals; Food industry and trade -- Periodicals; Food industry and trade -- Canada -- Periodicals; Food Technology -- Periodicals; Food -- Periodicals; Food-Processing Industry -- Periodicals; Aliments -- Industrie et commerce -- Périodiques; Aliments -- Industrie et commerce -- Canada -- Périodiques; Aliments -- Recherche -- Périodiques; Food industry and trade; Canada; Periodicals; Electronic journals; 664.005
• DOI: 10.1016/j.foodres.2022.112080
• Languages: English
• ISSNs: 0963-9969

Abstract

Graphical abstract: Highlights: Hay-like off-odor was peceived during both thawing and drying processes of basil. 3-Methylnonane-2, 4-dione was identified as a contributor of hay-like off-odor. Light and oxygen protection reduced the formation of 3-methylnonane-2, 4-dione. Abstract: Hay-like off‐odor present in dried basil products results in low consumer acceptance. To understand the hay-like off-odor formation in processing of basil products, identification of hay-like off-odor in thawed, air-dried and spray-dried basil samples was investigated by means of a trained human panel ( n = 10) and gas chromatography–mass spectrometry–olfactometry. 3-Methylnonane-2, 4-dione (3-MND) was identified in all basil samples to be responsible for the hay-like off-odor. To reduce the hay-like off-odor in dried basil products, the effect of light, oxygen, and temperature on the 3-MND formation was studied during thawing, air drying and spray drying processes. In the thawing process, darkness and nitrogen protection significantly reduced the 3-MND formation. With extending thawing time, no significant increase on the concentration of 3-MND was observed after 60 min in the darkness and under nitrogen. In the designed spray-drying setup, nitrogen protection could further alleviate the 3-MND formation whereas the elevated drying temperature (40–100 °C) boosted the 3-MND formation in air-drying processing. Collectively, these findings indicated that darkness, nitrogen protection and low temperature were considered as critical processing parameters to minimize the generation of hay-like compound 3-MND in dried basil products.